1. Field of the Invention
This invention relates to fiber optic communication, and more particularly, to transimpedance amplifiers used in formatting fiber optic communication data.
2. Description of Related Art
Low-cost, high-performance, highly integrated fiber optic interface circuits are becoming increasingly necessary to meet the demands of high-speed digital data communication. With the advent of Gigabit Ethernet systems, for example, fiber optic technology has become increasingly preferred. One standard circuit function for fiber optic communication systems is a transimpedance amplifier that is used within an optical receiver. Transimpedance amplifiers are employed in optical receivers in order to convert very small currents indicative of optical signals applied to photodiode detectors. These small currents are then converted to signal voltages of greater amplitude. In an optical fiber communications network where a plurality of geographically distributed users each write onto a common optical fiber, incoming optical signals from a nearby transmitter may be detected at a high signal level, whereas incoming optical signals from a distant transmitter may be detected at very low signal levels. As such, to be effective, a transimpedance amplifier desirably should be able to detect all levels of signals and transmit these signals without loss of signal bandwidth to components that are physically distinct from the transimpedance amplifier.